private void cboSoHopDong_TextChanged(object sender, EventArgs e) { _KTCNHopDongRepo = new KTCNHopDongRepo(); var list = _KTCNHopDongRepo.GetAllToList(); AutoCompleteStringCollection auto1 = new AutoCompleteStringCollection(); foreach (var item in list) { auto1.Add(item.SO_HD); } cboSoHopDong.AutoCompleteMode = AutoCompleteMode.SuggestAppend; cboSoHopDong.AutoCompleteSource = AutoCompleteSource.CustomSource; cboSoHopDong.AutoCompleteCustomSource = auto1; }